Thailand – Landlines and Mobile Phones

What are Thailand’s international dialling codes, and which area codes apply to the most popular expat destinations?

Thailand’s International Subscriber Dialling (ISD) code is 66. To call Thailand from overseas, you first dial your country’s international exit code — typically 00 in most parts of the world, or 011 if you are calling from North America — then 66, followed by the local number without its leading zero.

Thailand uses +66 as its country code and 0 as the domestic trunk prefix, and the country operates a closed dialling plan. This means that when dialling within Thailand, you must always use the complete national number including the area code, even when calling from within the same city or district. For fixed lines, Bangkok and its surrounding provinces use the single-digit area code 2, while all other regions use two-digit area codes. Subscriber numbers in the Bangkok 02 zone are typically seven digits, while those in other areas are commonly six digits.

A Thai mobile number such as 081 234 5678 in domestic format becomes +66 81 234 5678 when dialled internationally — simply remove the leading zero and add +66. The same principle applies to landlines: the Bangkok number 02-123 4567, when dialled from outside Thailand, becomes +66 2 123 4567.

The table below lists area codes for the main destinations where expatriates tend to settle in Thailand:

Thai fixed-line numbers contain nine digits in total, while mobile numbers have ten digits — both figures include the leading trunk prefix “0”. Because Thailand uses a closed national dialling plan, the full area code must always be dialled regardless of whether you are calling locally or from a different part of the country.

When placing international calls from Thailand, the outgoing exit code is 00. From a mobile phone, you can use the + symbol in place of 00 to ensure the format works universally. Thailand also has a number of carrier selection prefixes available for landline users — such as 001 (via the CAT/NT gateway), 007, and 008 — which can offer discounted rates on international calls when dialled ahead of the destination number.

Who are the main fixed-line telephone providers in Thailand, and how can you reach them?

Thailand has three fixed-line telephone operators: the state-linked National Telecom (NT), True Corporation, and 3BB (previously known as TT&T). The availability of each operator depends on your location, so it is worth checking which company has infrastructure in your specific area before signing up for any service.

National Telecom (NT) is Thailand’s largest fixed-line provider by active subscriber numbers and serves both Bangkok and the provinces. NT came about through the merger of two state enterprises — TOT and CAT Telecom — and also manages key international gateway infrastructure. You can reach NT through their website at www.ntplc.co.th or by phoning their customer service line on 1888.

True Corporation offers fixed-line services with a particular concentration in Bangkok. True is a large private telecommunications group whose offerings typically bundle landline access together with broadband internet and pay-television. Their website is www.true.th and their support line is 1686. True is often a practical option for residents of Bangkok condominiums and newer housing developments where the company’s fibre network is already in place.

3BB (the trading name formerly associated with TT&T) specialises in fixed-line and broadband services in provincial Thailand, making it a familiar choice for expatriates living in Chiang Mai, Chiang Rai, and across the central and northern regions. AIS has been strengthening its fixed broadband position through its acquisition of 3BB, enabling service bundling across mobile, internet, and entertainment platforms. For more information, visit www.3bb.co.th or call the 3BB hotline on 1530.

Tariffs and available packages from all three providers are updated frequently. Always consult each provider’s official website for the most current pricing, as the details published here may no longer reflect the latest offerings.

Who are the main mobile phone providers in Thailand, and how can you reach them?

In 2023, True Corporation completed a corporate merger with DTAC — previously Thailand’s second and third largest mobile operators respectively. The result was a near-duopoly in which AIS and True (now incorporating DTAC) account for the vast majority of the country’s mobile market. AIS retains the lead by revenue, while True holds a slight advantage in total subscriber numbers and 5G deployment.

AIS remains the most prominent player in Thailand’s mobile market, with population coverage reported above 95% and a subscriber base exceeding 46 million as of late 2024. It is generally regarded as the superior network for reaching remote and rural locations, including border areas, island communities, and mountainous regions. Customers can reach AIS via www.ais.th or by dialling 1-2-Call (1200).

Following its merger with DTAC, True Corporation reported approximately 48.5 million subscribers by mid-2025, making it the largest operator in Thailand by customer count. TrueMove H delivers strong performance in urban environments and along major roads, and frequently achieves the highest 5G speeds — often in the range of 100–200 Mbps in Bangkok. Details on plans are available at www.true.th, and customer service can be reached on 1242.

DTAC continues to operate as a distinct brand under the True Corporation umbrella and is generally seen as the most affordable option among the three networks. It performs well for users based in Bangkok, Chiang Mai, Pattaya, and other major urban centres. DTAC plans can be found at www.dtac.co.th or by calling 1678.

National Telecom (NT) also has a mobile arm and provides international long-distance calling services. NT’s mobile network is smaller in scale than either AIS or True, but it plays a key role in providing infrastructure support to MVNOs — smaller virtual network operators that lease capacity from the main providers. You can reach NT at www.ntplc.co.th or on 1888.

All mobile connections in Thailand now qualify as broadband services, operating on 3G, 4G, or 5G technology. Plan pricing and promotional packages shift regularly across all operators, so always confirm the latest tariffs directly with the relevant provider before committing to a plan.

Mobile telecommunications in Thailand fall under the regulatory authority of the National Broadcasting and Telecommunications Commission (NBTC), which is responsible for licensing, consumer protection, and service quality standards.

How do I arrange a landline connection in Thailand?

Setting up a fixed telephone line in Thailand follows a fairly clear process, though the exact steps can differ depending on which provider operates in your area and whether an existing line is already in place at your property. Whether you own or rent your home will also affect what documentation is required.

1. Select your provider. Start by identifying which company serves your location. NT covers most of the country, True concentrates on Bangkok, and 3BB is the usual option across many provincial areas. Not every provider operates in every location, so confirming coverage before you apply is essential.
2. Go to a provider office or retail outlet. Foreign nationals applying for a new fixed line must attend a provider office in person. Both NT and True have service counters in many shopping centres across Thailand where you can submit an application directly.
3. Gather the required documents. Foreign nationals applying to connect a new line — or to reconnect an existing one — at a property they own or lease must present a valid passport, a copy of their work permit (where applicable) or a Certificate of Residence issued by Thai Immigration, or alternatively a letter of residence from their Embassy certified and translated into Thai. A copy of the lease agreement or title deed is also needed.
4. Provide supplementary documentation if renting. Tenants must also supply a letter from their landlord and a copy of the landlord’s House Registration Document (Tabien Baan). In practice, many landlords prefer to set up the telephone line themselves and include the cost in the monthly rent, which can simplify things considerably for the tenant.
5. Pay any required deposit or set-up fee. A one-time installation fee may apply when setting up a new landline. Enabling international calling access may also require an additional deposit. Speak directly with your chosen provider at the time of application to confirm the amounts, as these figures are subject to change.
6. Wait for the installation appointment. Once your application has been processed and any upfront payment made, the provider will arrange for an engineer to attend and connect or activate the line. In cities, this typically happens within a few days to a week; rural locations may take longer.
7. Apply for international dialling separately if required. A newly installed landline will allow you to make domestic calls immediately. However, the ability to dial international numbers may need to be applied for separately and may require an additional deposit before it is activated on your account.

Always verify the current requirements with your chosen provider before applying. You can also contact the NBTC for independent regulatory guidance. Processes and fees may have been updated since this article was written.

How do I obtain a mobile phone SIM card or contract in Thailand?

Buying a mobile SIM card in Thailand is a remarkably straightforward process by international standards. SIM cards are sold at operator stores in shopping malls and airports, as well as at 7-Eleven and Family Mart convenience stores and many independent mini markets. This accessibility — comparable to countries like Japan or South Korea — means you can have a working Thai number within minutes of landing.

SIM registration is compulsory in Thailand and is enforced strictly. When purchasing a SIM, you must present your passport, and providers will collect biometric data including fingerprints and a facial scan. This is a more involved process than in many other countries where simply providing a name and address suffices, so make sure your passport is readily accessible at the point of purchase.

At Suvarnabhumi Airport in Bangkok, all three major operators have prominent counters in the international arrivals hall just beyond customs, positioned close together for easy comparison, with additional stalls accessible before you clear customs. Picking up a SIM on arrival is therefore very convenient. AIS SIM cards are priced between 50 THB and 1,490 THB through resellers such as petrol stations, convenience stores, and grocery shops (figures current as of 2025).

Prepaid (pay-as-you-go) SIMs are the most popular choice among newcomers and all three major networks offer a range of prepaid packages with bundled data, voice calls, and SMS. Tourist SIM cards with fixed validity periods of 7, 15, or 30 days are widely stocked. For those planning a longer stay, postpaid (contract) plans provide monthly billing and are available from all major operators, though they generally require a Thai bank account or credit card and a confirmed residential address.

Unlike some countries where postpaid contracts are tightly restricted by residency status or credit history, Thailand’s operators are broadly open to offering monthly plans to foreign nationals on valid non-immigrant visas. Short-term visitors and tourists are typically limited to prepaid options. If you hold a longer-term visa — such as a retirement visa, work permit holder status, or Thailand Elite membership — a postpaid contract is usually within reach. Confirm current requirements with the operator directly, as terms can vary between plan types.

Thai prepaid SIMs must be topped up at least once every 45 days, or you must pay to extend the validity period, to prevent the number from being deactivated. Additionally, at least one outgoing call or SMS must be made every six months to keep the account active. This is worth bearing in mind if you use a secondary SIM or keep a Thai number as a backup.

How do I pay my telephone bill in Thailand?

Telephone bills in Thailand are issued monthly and can be settled through a variety of channels: in person at a telecom provider office, by direct debit, via internet or telephone banking, at a bank branch, by cheque sent by post, by credit card, by ATM transfer, or at a post office. This breadth of options is broadly similar to what you would find in other well-developed telecoms markets, though payment at post offices is a particularly Thai-flavoured convenience worth knowing about.

The most common approach for most residents is to pay online or through the provider’s dedicated mobile app. All three major operators — AIS, True, and NT — offer polished apps that support account top-up, bill settlement, and plan management directly from your phone. Some providers also accept in-person payment at authorised retail outlets and dealerships.

Not every bank or credit card is accepted by every telecoms provider, so it is advisable to check which payment methods your chosen company supports. This matters especially if you only hold a foreign-issued card, as Thai provider payment portals do not always accommodate international cards. Opening a Thai bank account as early as possible after relocating will make managing bills considerably more straightforward.

For those who have not yet set up a Thai bank account, Rabbit LINE Pay — a digital wallet integrated into the LINE messaging app — offers a practical workaround. It accepts foreign Visa, MasterCard, and JCB cards and can be used to top up AIS or DTAC accounts with no additional transaction fee, making it a useful tool for managing prepaid credit in the interim.

Always check your provider’s billing terms, available payment methods, and payment deadlines, as late payments may attract additional charges or lead to service suspension. Prepaid customers do not receive a traditional monthly bill; instead, they need to maintain sufficient credit to keep services running. Postpaid customers receive a monthly invoice and are generally given a short grace period beyond the due date, though disconnection timelines differ between operators.

What practical advice should newcomers know about using phones in Thailand?

Network quality and coverage: AIS holds the top position in Coverage Experience among Thai operators, with the broadest geographic footprint across populated areas. DTAC leads the Reliability Experience metric according to independent assessments by Opensignal. TrueMove H performs particularly well in Bangkok and other major cities but can be inconsistent in more remote parts of the country. For expatriates living in rural areas, on islands, or close to Thailand’s land borders, AIS tends to offer the most dependable signal.

eSIM availability: All three major networks now support eSIM on compatible handsets, meaning you can arrange a Thai connection before you even touch down in the country. Third-party eSIM providers also offer plans using Thai network infrastructure and may provide greater flexibility on data volumes and validity periods. eSIM is particularly handy if you wish to keep your home-country number active on one profile while running a Thai number on the other — though biometric registration requirements still apply for eSIM activations done within Thailand.

Number porting: If you already have a Thai mobile number and wish to move it to a different operator, mobile number portability (MNP) is available and is overseen by the NBTC. The transfer typically takes a few working days — longer than in countries such as Germany or France where porting can complete within a single business day. For up-to-date procedures and timelines, consult the NBTC website.

International roaming: Using your home network while in Thailand can generate substantial roaming charges. If you are relocating on a semi-permanent or permanent basis, switching to a local Thai SIM or postpaid plan will save you a significant amount compared with staying on an international roaming arrangement. All three major operators provide roaming packages for when Thai residents travel abroad.

Keeping a foreign number active: Dual-SIM smartphones are extremely prevalent in Thailand and allow you to run a foreign number alongside your Thai SIM. Devices with eSIM capability can handle both simultaneously without needing a physical second SIM slot. Many long-term residents maintain a home-country SIM on a low-cost or data-only plan primarily for messaging apps, while relying on their Thai number for all calls and local data use.

Wi-Fi availability: Public Wi-Fi hotspots are widely distributed across Thailand, with free access available at cafés, restaurants, hotels, and shopping centres throughout the country. This strong Wi-Fi infrastructure can reduce day-to-day reliance on mobile data. Most major operators also offer Wi-Fi access as part of their SIM plan bundles.

Phone etiquette and local customs: Mobile phone use is thoroughly woven into everyday life in Thailand, and it is perfectly normal to use your device in restaurants, on public transport, and in most social situations. The LINE messaging app is the dominant platform for personal and professional communication in Thailand and is used by businesses, government agencies, and individuals alike. Installing LINE and registering it with your Thai number early on will help you slot into local communication habits quickly.

Emergency numbers: The key emergency contact numbers in Thailand are 191 (police), 1669 (medical emergencies), 199 (fire service), and 1155 (Tourist Police, who offer assistance in multiple languages). All of these numbers can be dialled from any mobile phone even without a SIM balance or active credit.

Frequently Asked Questions

Can I keep my foreign number when I move to Thailand?

It is not possible to transfer or port a foreign mobile number into the Thai network — number portability in Thailand operates only between domestic operators. That said, you can keep your overseas SIM running by maintaining a low-cost or data-only plan from your home country, then add a Thai SIM or eSIM alongside it on a dual-SIM handset. Many long-term residents in Thailand manage both numbers simultaneously, using their foreign number for communication with family and friends abroad and their Thai number for all local calls and data.

Do I need a local address to get a SIM card in Thailand?

A permanent local address is not strictly necessary for a standard prepaid SIM — your passport serves as the primary form of identification at the point of purchase. However, a verifiable address may be required in certain registration scenarios, and it is typically expected for postpaid contract applications. If you are signing up for a longer-term monthly plan, having a Thai address such as your rental property will smooth the process and is usually needed for billing purposes.

Can tourists buy a SIM card in Thailand?

All three major operators sell tourist SIM packages through airports, convenience stores, and official retail outlets, including dedicated tourist SIM cards from AIS. A valid passport is required at the point of registration. Tourist SIMs come as prepaid cards with set validity windows and defined data allowances rather than open-ended monthly plans.

How long does it take to get a landline installed in Thailand?

In well-connected urban areas — Bangkok, Chiang Mai, and Phuket among them — installation is generally completed within a few days to about a week from the point at which your application and supporting documents have been accepted. In more remote areas, timelines can stretch longer depending on the state of local infrastructure. It is sensible to approach your chosen provider well ahead of when you need the line to be active, particularly if the property has no existing telephone connection in place.

Which mobile network has the best coverage in rural Thailand and on the islands?

AIS provides the most extensive nationwide coverage, maintaining a strong presence in cities and rural areas alike, with around 95% population coverage and broad 5G availability across nearly all provinces. For expatriates living on islands such as Koh Samui, Koh Chang, or Koh Lanta, or in smaller towns in the northern highlands, AIS is widely considered the most reliable option for consistent signal quality.

Is it possible to get a postpaid mobile contract without a work permit?

Several operators will provide postpaid contracts to foreigners who hold a valid non-immigrant visa — such as a retirement or education visa — even without a work permit. That said, policies vary across providers and can differ depending on which plan you are applying for. A passport, a Thai address, and in many instances a Thai bank account or locally issued credit card are typically required. Visiting an official operator store and asking directly is the best approach, as eligibility criteria and documentation requirements can change over time.

How do I contact the Thai telecoms regulator if I have a complaint?

Consumer complaints relating to telecommunications services in Thailand are handled by the National Broadcasting and Telecommunications Commission (NBTC), an independent state body responsible for overseeing the sector. You can submit a complaint through the NBTC’s official website or reach them directly by calling their hotline on 1200.

Are eSIMs widely supported in Thailand?

Yes — eSIM functionality is available through AIS, TrueMove H (True), and DTAC (now part of True), and is also offered by a range of international eSIM providers that operate using Thai network infrastructure. eSIM is especially convenient for new arrivals, as certain plans can be purchased and set up online before you depart your home country. Keep in mind that activating an eSIM through a Thai operator in-country still requires biometric identification, meaning a visit to an operator store may be necessary to complete the registration process.